Comparison of central corneal thickness in corneal edema by ultrasound pachymetry, specular microscopy, and anterior segment optical coherence tomography

Abstract

PURPOSE: The purpose of this study was to compare ultrasound pachymetry Ultrasound pachymetry (UP), specular microscopy (SM), and anterior segment optical coherence tomography (ASOCT) in the measurement of central corneal thickness (CCT) in cases of corneal edema before and after uncomplicated phacoemulsification. METHODS: Preoperative pachymetric measurements were performed in all patients before cataract surgery. Sixty -seven patients who developed corneal edema after routine faoemulsification surgery were included in the study. CCT measurements were made the day before surgery and on the 1 st , 7 th , and 14 th days after surgery. Correlation and agreement between the devices were quantified with the intraclass correlation coefficient (ICC), limits of agreement, and Bland–Altman plots. RESULTS: The mean age of the patients was 70.99 ± 9.56 (36–92) years. While CCT could be measured in all eyes with ASOCT after surgery, the number of eyes measured with UP and SM were 24 (11.7%) and 27 (16.1%), 55 (82.1%) and 52 (77.6%), and 46 (88.8%) and 45 (86.9%) on postoperative days 1, 7, and 14, respectively. ICC values between UP and SM, UP and ASOCT, and SM and ASOCT, respectively, were: preoperative 0.91, 0.94, and 0.92; 1 st postoperative day 0.93, 0.86, and 0.93; 7 th postoperative day 0.94, 0.85, and 0.96; and 14 th postoperative day 0.95, 0.92, and 0.96. CONCLUSION: In all eyes with corneal edema, CCT measurements can be taken with ASOCT; however, in some cases, CCT measurements with SM and UP cannot be taken. However, there is a good correlation between measurements taken with these devices.